As nouns the difference between shank and barrel
is that
shank is the part of the leg between the knee and the ankle while
barrel is (countable) a round vessel or cask, of greater length than breadth, and bulging in the middle, made of staves bound with hoops, and having flat ends or heads sometimes applied to a similar cylindrical container made of metal, usually called a drum.
As verbs the difference between shank and barrel
is that
shank is (archaic|ulster) to travel on foot while
barrel is to put or to pack in a barrel or barrels.
As an adjective shank
is (slang) bad.